1. Technical Field
The present invention relates to a signal processing device, a detection device, a sensor, an electronic apparatus, a moving object, and the like.
2. Related Art
Gyro sensors for detecting a physical quantity changing due to external factors are built into electronic apparatuses such as digital cameras and smartphones, and moving objects such as vehicles and airplanes. Such gyro sensors detect a physical quantity such as angular velocity, and are used in so-called shaking correction, posture control, GPS autonomous navigation, and the like.
A gyro sensor outputs the detected physical quantity such as an angular velocity as a detection voltage signal. The application side receiving the detection voltage signal integrates the angular velocity and the like, obtained by the detection voltage signal, using software processing, and obtains an angle, a velocity, a distance, and the like.
A DC offset caused by, for example, the temperature characteristics or the like of a physical quantity transducer is present in a detection voltage signal from the physical quantity transducer. There is a problem in that the DC offset causes an error when desired information is obtained from the detection voltage signal. For example, in the aforementioned gyro sensor, since the detection voltage signal including the DC offset is integrated during the obtaining of an angle and the like, a great increase in error is brought about.
As a method of removing a DC offset, JP-A-2004-347505 discloses a method of processing a detection voltage signal using a high-pass filter. In addition, JP-A-2002-236302 discloses a method of adding a bias having a predetermined voltage to the detection voltage signal. However, since the characteristics of the high-pass filter are fixed in the method of JP-A-2004-347505, there is a problem of the characteristics influencing the transient responsiveness of the detection voltage signal. In the method of JP-A-2002-236302, there is a problem in that it is difficult to follow a change in the DC offset.